Most mobile construction machines have an above-hood air intake. The above-hood air intake is usually covered by a shield to prevent the entrance of rain and other precipitation. Above-hood air intakes are typically designed to be low profile, i.e., evince a small signature. However, these intakes are required to be high enough to minimize the entry of dust and other debris settling near the hood and far enough from the exhaust stack associated with these machines to minimize the intake of preheated air. Pre-cleaners are typically available for above-hood air intake designs and are used to remove some of the debris from the intake air and, thusly, extend engine air filter life.
Some mobile construction machines are provided with conventional under-hood air intake systems having air intake tubes with inlet openings located in the engine compartment. When these systems have perforations in the hood of the engine compartment, the inlet opening is arranged to prevent the intake of rain and other precipitation. Thus, the inlet opening of the air intake tube is angled such that intake air enters in a direction that is horizontal to or at least partially opposite to the direction of the precipitation as it enters the engine compartment. Other under-hood air intake designs include air intake tubes that are routed to compact cooling package areas where the air inlets are located in areas separate from the engine compartment.